Apparatus for drying or cooling materials



ll 1 ll June 2, 1936. o. s. ANDERSON ET AL 2,043,143 APPARATUS FOR DRYING OR COOLING MATERIALS Filed Jan. '7, 1935 5 Sheets-Sheet l June 1936- o. SPANDERSON El AL 2,043,143

APPARATUS FOR DRYING OR COOLING MATERIALS Filed Jan. 7, 1955 5 Sheets-Sheet? mm W m r m w W .W 3 k .8 m Q J 5 O M Q :MQ

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APPARATUS FOR DRYING OR COOLING MATERIALS Filed Jan. '7, 1935 5 Shets-Sheet s Zhwentor;

attorneys June 2, 1936. o. s. ANDERSON ET AL 2,043,143

APPARATUS FOR DRYING OR COOLING MATERIALS Filed Jan. 7, 1935' 5 Sheets-Sheet 4 attorneys J 1936- 0 s. ANDIERSON ET AL I 2,043,143

APPARATUS FOR DRYING OR COOLING MATERIALS Filed Jan. 7, 1935 5 Sheets-Sheet 5 Patented June 2, 1936 UNITED STATES PATENT OFFICE APPARATUS FOR DRYING OR COOLING MATERIALS ration of Ohio Application January 7, 1935, Serial No. 776

25 Claims. (01. 257-79) This invention pertains to heat transfer apparatus, and more particularly to that type wherein a fixed shell or casing is employed within which a cage of pipes is placed and is rotatable with reference to the shell or casing, means being provided to supply said pipes with the heating or cooling medium.

In addition to the foregoing, the structure provides means for cascading the material over the cage of pipes as they are rotated as a whole within the casing, and provides scrapers for maintaining the pipes free of any accumulated material which would tend to cut down their efliciency, and, consequently, the capacity of the apparatus.

The invention also has for its object the provision of driving means'for the cage of pipes as well as the scrapers located primarily exteriorly of the casing, and, therefore, not subject to the deteriorating effect of the temperature obtaining within the casing.

With a view of simplification of the description, the structure will be hereinafter referred to as a drier, and reference will be had to the annexed drawings, wherein:

Figure 1 is a side elevation of the drier, the parts being entirely enclosed by the casing;

Fig. 2, a top plan view thereof;

Fig. 3, a horizontal sectional view of the forward or infeed end of the drier upon a somewhat larger scale than that shown in Figs. 1 and 2, the section, insofar as the scraper element is concerned, being taken on the line III-III of Fig. 7;

Fig. 4, a similar View of the discharge end, said views 3 and 4, when read together, showing a horizontal section of the complete machine;

Fig. 5, an end elevation of the machine at the head end thereof, with parts partly broken away;

Fig. 6, a vertical sectional View taken on the line VIV'I of Fig. 4, and illustrating the lower portion of the supporting framework and the trough of the drier; 1

Fig. 7, a vertical sectional view, partly broken away, taken on the line VII-VII of Fig. 3, and illustrating more particularly the construction of the head-end scraper and associatedelements;

Fig. 8, a face view of one end of a motiontransmitting structure employed to impart rotary movement to the steam head located at the discharge end of the drier and to which the pipes are secured;

Fig. 9, a similar view of the same structure as seen from its opposite end;

Fig. 10, a detail view, partly in section, showing a scraper in the form of a coil spring encircling one of the heating pipes, the spring being illustrated as just contacting the steam head and being in its fully extended position;

Fig. 11, a similar view with the spring in a compressed condition; and.

Fig. 12, a detail sectional view on a somewhat enlarged scale, showing the means employed to impart reciprocatory motion to the driving shaft, together with the shear pin construction employed in conjunction therewith.

In the drying of certain classes of material, it is, of course, essential that the material be agitated and caused to move from the inlet to the outlet of the drier, if the drier is to be a continuously acting one.

Certain materials, as will be readily appreciated, are more or less adherent to the various elements of a drier mechanism, and particularly so to the heating elements thereof, such as pipes or the like, cutting down the efficiency of the drier unless it be that the heating elements are kept clean and free of any accumulated material.

The structure in the annexed drawings and hereinafter described, provides a drier which, while highly eificient in operation, is relatively simple of construction and easy of assembly.

In the drawings, Ill denotes the base of the machine provided with two longitudinally extending beams II and I2, to which and to the base III, is secured a bottom or trough-like member I3 (see more particularly Fig. 6).

At the head end of the machine, the trough is provided with a vertically disposed end plate I4 having a semi-circular opening formed in the upper marginal portion thereof for the reception of certain operating elements, hereinafter referred to. At the opposite end of the machine, the lower portion of the trough is provided with a "similar plate I5. A pair of transversely extending structural elements I6 and I! are secured to the side beams I I and I2 at the head end of the machine, and similar members I8 and I9 are secured to said side frame members at the discharge end. These members, I6, I! and I8, I9, form, in effect, the main supporting elements for the bearing members hereinafter referred to. a I

The upper edges of the trough-shaped member I3, as well as the end plates I4, I5, are formed with outwardly extending flanges which form the support for the upper housing of the structure denoted generally by 20, Figs. 1, 2, and 5, the roof 2| whereof inclines upwardly toward the center and opens into a duct or offtake 22, the upper wall whereon inclines upwardly and in the 575 lower portion of which there is provided a pocket or trap 23 having a removable receptacle 24. This arrangement precludes the inflow of moisture which may condense in the stack and drop downwardly, and tend to reflow into the drier. Should dust collect in this portion of the apparatus, the receptacle 24 maybe removed from time to time as occasion requires, and cleaned out. This trapping of the moisture prevents its return to the drier, as just above mentioned, and, consequently, it is not necessary to re-evaporatethe same.

Air is admitted into the body or shell of the drier through suitable openings as 25 (see more particularly Fig. 6), formed in the upper portion of the trough-shaped member and protected by deflector plates 26 which extend upwardly and outwardly away from the openings, to prevent the egress of material through such openings. Natural draft through the drier, under most conditions, will be found all-sufiicient, doing away .with the necessity of theuse of a fan.

At the discharge end of the drier, there is provided a discharge opening 21 (Figs. 1-6), with which is associated any suitable offtake mechanism, as for instance an endless conveyer designated by 28. It will be understood, of course, that the showing is merely indicative and not complete in this respect.

Mounted upon and secured to the elements It and I1 of the frame structure is a motor 29, the shaft. whereof carries a pinion 3| meshing with a large gear 32rigidly affixed to a casting or member 33,. shown as cored out in part, to make it relatively light. Said casting is keyed to a hollow shaft 34 mounted for rotation in a pillow block 35 secured to the frame members l6and l1, suitable bronze bearing elements 38, 31 being interposed between said shaft and the pillow block.

This arrangement carries the weight of the parts at the intake or head end of the machine.

At its outer end, shaft 34 is provided with an outwardly projecting flange or collar 38, to each side of which and within the pillow block are mounted, bronze thrust washers 39, 4|, which are held in place in a recess formed in the rear end of the pillow block. Bearing against washer 4| is a ring-shaped element 42, partially seated within a sleeve-like member 43 and also within the pillow block 35. A split ring 44 is partially seated in the innerend of the member 43 and bears against the ring 42, holding the same against adjacent thrust washer 4|.

Member 43, as will be best seen upon reference to Fig. 3, is provided with an outwardly extending flange which is bolted to a. similar flange formed upon the pillow block 35. The exterior of the split ring 44is partially seated in the adjacent face of the ring 42, and likewise in the inner end of the sleeve 43, while the inner portion or said ring is seated in a groove formed exteriorly of a second sleeve-like member 45, the inner end whereof is seated in the sleeve 43. Member 43 is provided with an outwardly projecting element 46 (see Fig, 12) which stands opposite when the parts are in normal position, to a similar projection 41 formed upon the member 45. Said projections are formed with oppositely disposed openings in each of which there is mounted a tubular member 48, 49, respectively, preferably formed of hard steel and extending through which is a shear pin 5! produced from a softer steel.

Inasmuch as the member 43 is rigidly affixed to the pillow block 35* by being bolted thereto, the member 45 is held against rotation so long as the shear pin remains intact. Member 45 has a square socket formed therein for the reception of a bushing 45 which forms a bearing for a stem 52 of a shoe 53. Said shoe works in the intersecting grooves 54, 55 of a reversing-motion cam formed in the outer portion of a shaft 56, or more specifically, in a separate piece formed as an extension thereof. A suitable housing 51 is provided forthe outer portion of the shaft, upon which the cam grooves are formed, as best shown in Fig. 3. By forming the spiral upon a separate element and securing it to the main shaft 56, machining is facilitated and smaller pieces of stock may be utilized and more easily replaced when worn.

Shaft 55 (Fig. 3) extends inwardly of the casing through a bronze or other suitable bushing 58 mounted in the interior of the inner end of the hollow shaft 34. A cap nut 59, together with suitable packing BI, is secured upon the exterior of the inner end of shaft 34, preventing ingress of material to the interior of the shaft 34 as the shaft 56 is reciprocated back and forth through the nut and hollow shaft.

As noted at the outset, it is designed to have a cage of pipes rotated within the shell or casing, and to provide scrapers movable thereover, to keep the pipes clean and likewise to have means for cascading the material being dried over and upon the pipes.

As will be seen upon reference to Fig. 8, a plurality of plates, 3 in number, denoted by 69, are bolted directly to the innermost face of the member 33, as shown in Fig. 3. Extending from each of these members 69 and preferably secured thereto by welding, is a trough-shaped element 13 (see more particularly Figs. 3 and 7).

At their outer ends, these members 13 are rigidly aflixed, as by welding, to a spider frame 1!, having a centrally disposed hub 12 in which is mounted and secured a rigid shaft or rod 13, which extends toward the discharge end of the shell or casing, and is rigidly secured to a centrally disposed hub 14 formed as a part of a head denoted generally by 15 and provided with steam inlet and exhaust passages 16 and 11, respectively. The head is formed with a trunnion 18 which is mounted in a suitable bearing 19 secured to the cross frame members l8 and I9, heretofore referred to. Suitable steam inlet and exhaust pipes and passages are provided in connection with the trunnion bearing to supply steam to and exhaust steam from the passage 16 and 11, respectively.

Secured to and extending longitudinally of the shell or casing from the head 15 are steam inlet pipes 8| and arranged exteriorly thereof are the return pipes 82. At their opposite ends (see Fig. 3), the pipes 8! stop short of the ends of the pipes 82, which latter have welded or otherwise secured adjacent their ends, closure plugs 83.

Upon reference more particularly to Fig. '7, it will be seen that there are a number of these pipes arranged in two circular series about the axis of the structure, the pipes of one series standing in substantially staggered relation to those of the other, so that any material falling therebetween will come into contact with one or both of the series. The pipes, at the intake end of the machine, (Fig. 3), extend through openings formed in the outwardly extending portion of the platelike element of the scraper 84 (see Figs. 3 and 7 the hub whereof denoted by 85 is keyed to the reciprocating and rotatable shaft 56.

Intermediate the flange and the hub, the scraper may be said to be provided with a series of radiating spokes 86 (3 being shown), the outer ends whereof terminate in an inwardly projecting annular flange 81. The edges of these spokes will preferably be beveled, so as to produce a sharp cutting edge, for a purpose which will presently appear.

To assist in the rotative movement of thepipes, scraper elements and scoops, and likewise to maintain a proper alignment of the parts and prevent undue twisting strain being placed thereon, one or more of the spokes 86 may be provided with laterally extending arms 88 and 89 (see more particularly Figs. 3 and 7). One of the arms, as 88, is shorter than the other and has mounted in its outer end set screws as 98, provided with jamb nuts to hold the same in place. This makes it possible to adjust the parts with relation to each other, and while not permitting undue play, still have sufficient clearance between the arms and the adjacent walls of. the member l 8 to permit the arm 88 and the heads of the bolts to move along the face of the member I8 as the scrapers are moved forward and back.

Pivotally attached to each of the spokes 86 is a shackle 9 I, to which is rigidly afi'ixed a member 92, which for the sake of lightness, may be formed from pipe, and which at its opposite end has rigidly attached to it, a shackle 93 pivotally attached to a lug 94 carried by a ring 95, which latter, together with the lugs, is welded to a scraper plate 96 adjacent the discharge end of the machine.

As will be seen upon reference to Fig. '7, there are three pipes, as 92, and upon reciprocation of the head scraper 84, the scraper plate 96 will have imparted to it a similar reciprocatory movement. By employing three of such thrust and pull members 92, twisting and binding of the parts is obviated.

As will be seen upon reference to Figs. 4, 10, and 11, pipes 82 have exteriorly mounted thereon coiled springs 91, the springs occupying a position between the plate 96 and the head 15. The ends of the springs which abut the plate 96 are welded thereto so as to move with said plate and are thereby caused to travel over the pipes throughout the limit of travel of the plate 96 toward and from the head. This produces a scraping of the pipes which would not otherwise obtain throughout this section, and by reason of the fact that the springs are placed under compression as the plate 96 approaches the end of its travel to the right of Fig. 4, they will, upon release from such compression, tend to vibrate and free themselves and the pipes of any accumulated material.

In addition to the head scraper 84, as it may be termed, and the scraper plate 96, a number of intermediate scraper plates denoted generally by 98 will be utilized. These plates are of ringshaped form and are provided with a series of openings through which the pipes 82 pass, the openings being slightly larger than the outside diameter of the pipe, for reasons hereinafter specified, as are the openings in the scraper 84 and the plate 96. They may be interconnected in any suitable manner. In the instant case this connection preferably takes the form of a series of scoops produced from plates bent to the form best shown in Fig. 7, with the advancing edge thereof extending outwardly to a point substantially coincident with the outer edge of the plate 98 or beyond the fluted edge of the head scraper 84. These scoops are denoted generally by 99 and are held in position with relation to the head scraper 84 by studs or pins I88 which extend outwardly from the flanged end of the adjacent member 99 (see Fig. 3) and pass freely into openings formed in the scraper. As will be seen upon reference to both Figs. 3 and 4, the ends of the members 99 are upturned or outwardly flanged and are secured to the scrapers 98 and the scraper 96 by bolts I8I, the latter not being drawn up tight, thereby insuring flexibility of the scoop and scraper assembly.

By providing clearance between the studs I88 and the openings into which they project and the openings through which the pipes 82 extend, and likewise providing clearance between the pipes and the other-scraper elements throughout the length of the structure, a flexible assembly is provided which permits the scrapers to maintain their position upon the pipes through the action of gravity and conform to the sag of the pipes, which, of course, will inhere to some degree as the time of. use of the drier is prolonged.

As will be seen upon reference to Figs. 3 and 'I, a series of plates denoted generally by I82 are secured to the outermost face of the scraper 84 adjacent the periphery thereof, the advancing edge of each of said plates projecting out in the same general direction as that of the scoops 99. These plates I82 act as knives to cut up any material which may become impacted between the head end of the casing and the adjacent face of the scraper plate, 84. f

Depending upon the material undergoing treatment, the rate of feedv will vary. To this end, a variable feed mechanism denoted generally by I83is shown in Figs. 1', 2, and 5. Any form of such mechanism may be employed and will be driven through a sprocket chain I84 passing about a sprocket wheel I secured to the casting 33 (see more particularly Fig. 3), and likewise about a sprocket wheel I86 of the driving mechanism of the automatic feed.

The shell or casing will preferably be provided with panel-shaped doors I8'I (Figs. 1 and 2) at one side thereof, in order thatthe interior of the apparatus may be readily inspected.

A relatively small swinging door I88 (Figs. 1 and 6) will preferably be located in the side of the base I8 at the point of discharge, so that the operator may withdraw samples of the material with a view of ascertaining its condition and, consequently, determining whether or not the drier is operating in a proper manner.

The casing, preferably at the forward end thereof, is formed with an opening covered by a plate I89, bolted or otherwise secured to the casing. This opening affords access to the adjacent portion of the drier mechanism, in order that the pipes thereof may be removed or tightened up, as may be necessary.

It is thought from the foregoing description that the operation of the machine will be understood. A brief rsum, however, may be given.

Material passing through the feeder I83 will drop onto the pipes immediately therebeneath and onto the trough-shaped elements I8, and be carried around and thrown outwardly thereby; the parts being in theposition shown in Fig. 3.

As shaft 34 is rotated, rotary motion is imparted to the shaft 56 as well as a reciprocating motion through the action of the double spiral cam 54, 55. Rotation of the shaft 56 imparts rotary movement to the head scraping element 84, and, consequently, to the pipes 82. At the same time, the shaft 56 moves inwardly from the position shown in Fig. 3 and through the combined thrust and pull rods or bars 92, endwise movement is imparted to the scraper plate 96. Inasmuch as this plate is interconnected through the scoops 99 with the other scraper elements: 9.8 and also with the head scraper 84, rotative movement is imparted to the head 15, the cage of pipes and the various scrapers. mounted upon and primarily supported by said pipes.

Rotative motion is also imparted to. the head 15 through the shaft 13 which is pinned to the hub of the member 15, and to the corresponding hub 12 of the plate 'H, as heretofore described.

The intermediate scrapers 98 and the end scrapers 84 and 96, which are secured together by the intermediate scoops 99, carry said scoops around with them as the cage of pipes is rotated within the casing of the structure.

Through the action of the cam grooves 54, 55, shaft 56 and the parts attached thereto will be moved lengthwise in line with the axis of the machine, and as a consequence, the various scrapers will pass over the pipes which are fixedly attached to the head 15 and supported at various points throughout their length by the scraper member 84.

As the scraper plate 96 approaches its limit of movement toward the right (Fig. 4), the springs 91, which are in contact with the pipes 82, serve to scrape material therefrom, and the springs contacting the head element 15 will be placed under compression to a greater or less degree. Upon retrograde movement of the plate 95, the spring coils will become separated and a trembling movement will inhere, shaking off any material which may be adherent to said coils. Inasmuch as the material, when it reaches the discharge end of the machine at which the head 15 is located has been depleted, to a greater or less extent of its moisture, it is not, as adherent as it is at the infeed end of the drier, hence the spring scrapers will, in most instances, be found all-sufficient to maintain the exterior of the, pipes 82 clean.

As heretofore noted, the openings in the various scraper elements through which the pipes 82 pass are larger than the diameter of the pipes, hence the scraper assembly may adapt itself to any sagging or inequalities which may obtain in the pipes due to deformation by heat or otherwise. Moreover, the pipes being only rigidly supported at one end, as by the head 15, the scrapers will maintain good contact with the exterior of the pipes at all times, keeping the same clean and, therefore, in condition to readily bring about the proper heat transference.

As will be appreciated, the cage of pipes 82, 8|, rotates about the axis of. the machine. The scrapers and the scoops also rotate about said axis and, in addition to such rotary movement have, as above indicated, a reciprocating movement which follows a spiral path, moving first toward one end of the casing and then toward the other.

When the materials are first fed into the drier, they may be more or less sticky or adherent, and there may be a tendency for the material to become impacted between the scraper plate 84 and the adjacent end of the casing. To break up any such impacted material, the knives or plates I02 are employed. They have the effect of cutting up or destroying any compacted mass as they cut into the same, and, likewise, rotate through the mass as they are moving endwise into and out of the same, as the parts approach and leave the position shown in Fig. 3.

With a view of agitating the material at the head end of the drier, there is preferably secured to the member 33 one or more arms as H5, carrying at. their outer ends. inclined blades or paddles H6, The inner ends of the arms H5, extending into the member 33 and taking against a cross rib formed therein, thus serve with the securing bolts to maintain the parts in proper position.

By making the radiating spokes 86 sharp upon their faces adjacent the casting or member 33, the breaking up of any compacted material at this point is brought about and the sharpened forward edges of said members 86, as well as the edges of the arms 88, also prevent compaction of the material in and around the trough-shaped motion-transmitting elements 10 which might otherwise inhere when certain materials are treated.

It is to be noted that the actual driving mechanism or any part thereof which is likely to be disturbed or distorted by the heat obtaining within the drier, is located without the casing, and the parts are always readily accessible for repair or adjustment. If, for any reason, undue strain is placed upon the elements within the drier casing, as by undue compacting of the material, such strain will be imparted through the shaft 56 to the cam shoe 53, and through its support 52 to the element 45, in which it is seated, with the result that the shear pin 5! will be broken and further reciprocation of the shaft 56 stopped, inasmuch as the cam shoe becomes inactive and the member 45 is then free to rotate with the shaft 56. The shaft 55 will, however, continue to rotate.

While the structure has been denominated a drier, and is designed primarily for that purpose, it will be readily appreciated that the pipes 8|, 82 may be utilized to convey a cooling medium so that in the broader aspect of the invention and the claims, even though the term drier be employed, the structure as it is otherwise applicable is to be considered as a heat interchanger.

What is claimed is:

1. In combination with an enclosing shell or casing; a plurality of pipes located and rotatable within said casing; scrapers mounted upon and movable back and forth over said pipes; and a plurality of scoops associated with and partaking of the movement of the scrapers.

2. In combination with an enclosing shell or casing having an opening in the upper portion adjacent one end thereof for the introduction of material, and likewise having an opening in the lower portion thereof at the opposite end for the 5 discharge of material therefrom; a plurality of scoops located therein; and means for imparting endwise reciprocating movement to the scoops and likewise rotating them within the shell about the axis thereof.

3. In combination with an enclosing shell or casing having an opening in the upper portion adjacent one end thereof for the introduction of material, and likewise having an opening in the lower portion thereof at the opposite end for the discharge of material therefrom; a series of scoops located therein; and means for moving said scoops in an orbital path and at the same time imparting a reciprocating movement thereto in the direction of the length of the shell.

4. A structure as set forth in claim 3, wherein the scoops as they reciprocate follow spiral paths of movement about the axis of the casing.

5. In combination with an enclosing casing having an opening in the upper portion adjacent one end thereof for the introduction of material, and likewise having an opening in the lower portion thereof at the opposite end for the discharge of material therefrom; a series of scoops located therein; and meansfor moving said scoops through a spirally defined path extending longitudinally of the casing.

6. A structure as set forth in claim 5, wherein means is provided for moving the scoops back and forth within the casing.

'7. In combination with an enclosing shell or casing; a cage of pipes mounted for rotation therein; a series of scrapers mounted upon and movable over the pipes; a series of scoops connecting said scrapers; and means for reciprocating said scrapers and consequently the scoops longitudinally of the pipes.

8. A structure as set forth in claim 'Lwherein means is provided for imparting a spiral path of movement to the scoops during their reciprocation. 7 a.

9. In combination with an enclosing casing; a head located within the casing adjacent one end thereof and mounted for rotation, said head having inlet and exhaust passages formed therein; a a cage of pipes secured to said head, communicating with said passages and extending longitudinally within the casing; a series of scrapers mounted for movement over said pipes; a plurality of scoops interconnecting said scrapers; and means connected to at least one of said scrapers for imparting movement thereto longitudinally of the casing, and likewise imparting rotary movement to the cage of pipes and the head to which they are secured.

10. A structure as set forth in claim 9, wherein the means for imparting longitudinal movement to the scrapers comprises a reciprocating and rotating shaft.

11. A structure as set forth in claim 9, wherein coiled springs are secured to the face of the scraper next adjacent the head, said springs surrounding the pipes at least in part throughout the space existing between the head and the scraper to which the springs are secured when said scraper is moved away from the head.

12. In combination with a shell or casing, a head mounted for rotation therein adjacent one end thereof; at least one pipe secured to the head and extending longitudinally of the shell; a scraper mounted for movement over said pipe; and a coiled spring loosely encircling the pipe between the head and the scraper.

13. A structure as set forth in claim 12, wherein one end of the coiled spring is attached to the scraper, and the convolutions of the spring are separated while the spring is in its extended condition.

14. In a structure of the class described, the combination of a shell or casing; a head mounted for rotation within the casing adjacent one end thereof, said head having passages formed therein for the ingress and outflow of heating medium; a plurality of pipes connected to said head and in communication with said passageway, said pipes extending longitudinally of the shell or casing; a series of scrapers mounted upon and movable over said pipes; means for rotating the head; and means for reciprocating the scrapers.

15. In combination with an enclosing shell or casing, a head mounted for rotation within the casing adjacent one end thereof; a cage of pipes extending outwardly therefrom and supported thereby; a plurality of scrapers mounted upon and movable over said pipes, said scrapers likewise tending in part at least to support said pipes; a series of scoops associated with said scrapers; means for rotating the head; and means for reciprocating the scrapers. I

16. In combination with an enclosing shell or casing, heat transferring pipes located therein; at least one scraper movable back andforth over said pipes and toward the head end of the casing; means for moving said scraper; and at least one knife mounted upon and movable with the scraper,

said knife extending toward the head end of the scraper and serving as the scraper is reciprocated to cut up material which may be impacted between the scraper and the adjacent wall of the casing. 17. A structure as in claim 16, wherein means is provided for imparting rotary movement to said pipes about the axis of the shell or casing, to the scraper, and as a consequence to the knife.

18. In combination with an enclosing casing, a head mounted for rotation within the casing at one end thereof; a shaft mounted at the opposite end of the casing; means for imparting rotary and endwise movement to said shaft; a series of pipes connected at one end to the head and 5 extending longitudinally of the casing; and a series of scrapers mounted upon said pipes and movable thereover, at least one of said scrapers being directly associated with the shaft aforesaid to impart rotary movement to the pipes and head and also to the scrapers, and likewise to impart reciprocating movement to the scrapers, back and forth over the pipes.

19. A structure as set forth in claim 18, wherein scoops are directly associated with the scrapers. 20. In combination with an enclosing casing, a

head'mounted for rotation within said casing adjacent one end thereof; a cage of pipes extending outwardly therefrom and supported thereby; a shaft mounted at the opposite end of the casing; 40 means for imparting endwise and reciprocatory movement to said shaft; a series of scrapers mounted upon and movable over said pipes; means connecting the outermost scrapers to cause them to move in unison; scoops associated and movable with the scrapers; connections between one of said scrapers and the shaft aforesaid for imparting reciprocatory and rotary movement to said scraper and thereby to the other scrapers and scoops; and means independent of said scrapers for imparting rotary movement to the head.

21. In combination with a shell or casing, a head mounted for rotation within the shell adjacent the discharge end thereof; a shaft mounted at the intake end of the casing; means for imparting endwise and rotary movement to said shaft; a casting mounted for rotation at the intake end of the machine; a plurality of members secured to said casting extending inwardly of the casing in parallelism with the axis thereof; a frame-like structure connecting the inner ends of said members; a shaft connected thereto and extending therefrom to the head aforesaid; means for connecting said shaft to said head; a series of pipes secured to the head extending longitudinally of the casing; a series of scrapers mounted upon and movable over said pipes; a series of scoops located adjacent the outer edges of said scrapers and interconnecting the same in series; thrust and pull members connecting the innermost and outermost scrapers of the series; and a connection between the innermost scraper and the first named shaft.

22. In combination with an enclosing shell or casing, a head mounted for rotation in the casing edie eet. o e en h r o a e of pi es extemling outwardly therefrom and supported thereby; a plurality of scrapers having a series of openings therein through which the pipes extend, said openings being larger than the exterior dimensions of the pipes; means for rotating they head;

means for reciprocating the scrapers.

23. In combination with an enclosing shell or easing, a head mounted for rotation within the casing adjacent one end thereof; a cage of pipes extending outwardly therefrom and supported in llartat least thereby a plurality of scrapers, said scrapershaving openings formed therein through which the: pipes loosely p ss; a series of scoops associated with said scrapers; means for rotating the head; and means for reciprocating the scra e s- 24, In a drier, thecombination of an enclosing shell orcasing having at. least one air inlet adjacent the lower, portion thereof andwjth an offake. o po a ened i at. e ppe porti the eo an otatable means located within the shell for agitating and heating the material undergoing treatment, said means including a series of scoops with their inner ends extending toward the center of the casing, the outer ends moving in a path adjacent the air inlet and thereby serving to direct the air inwardly of the casing and outwardly through the offtake at the upper portion thereof.

25. In a drier, the combination of an enclosing shell or casing; a cage of heating pipes therein; means for moving said pipes bodily in a circular path within the casing parallel to the axis of rotation; a series of scrapers supported upon said pipes and movable thereover, the openings in the scrapers through which the pipes extend being. larger than the external diameter of the pipes; and means for moving the scrapers overthe pipes.

QRLIN S. ANDERSON. RAYMOND T. ANDERSON. 

